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Topic Review (Newest First)

07-24-2010 11:27 AM

simcros

carb cfm formula

So if I understand "techinspector1" correctly if I am running. A 350 @6000 rpm with 5 pnds boost, I'm running a B&M142, I should be running in the neighborhood of 800 cfm?

04-15-2010 10:53 PM

1932bantam

that type in pic is a draw thru turbo setup .not very good the fuel and air go thru the turbo instead of just air as in a blow thru. if you run one turbo has got to have the carbon seal in it or your in trouble

04-15-2010 09:46 PM

cobalt327

Speaking of supercharging stock engines, the set up below is a Turbosonic sold by Accel (among others) back in the 70's. The one shown was posted by a member here, upstand2. He has one like it and says it's "peppy". They show up on eBay for a couple hundred on up to several hundred more if all there, etc.

One on a SBF:

04-15-2010 08:06 PM

techinspector1

Yep, you can. In addition to what Blazin72 said, you must also lower the total ignition timing and control it according to the boost you use and make certain that you never go lean on the fuel air mixture.

In addition, you must realize that the motor is taking in more fuel air mixture because it thinks it is a bigger motor, so at some point you have to increase the CFM capability of the carburetor. There is a formula to determine the carb you need for a certain engine size, engine speed and blower boost.
{(CID x RPM) / 3456} x {(BOOST / 14.7) +1}

04-15-2010 01:56 PM

Blazin72

Despite the fact that this thread is now 7 years old I will answer your question for you.

Yes. As mentioned earlier, the smaller superchargers available (specifically the 142/144s) will work just fine on a stock engine and still give you a large horsepower increase, as long as you keep the boost reasonable.

04-15-2010 01:29 PM

tylerv350

stock 350?

There have been a bunch of small block chevy blowers on Ebay this month...Many went for under $800, most went for under $1300. The mini blower gives a quick and hefty horsepower/torque boost to mild engines.

People will tell you about the need for forged pistons, big rods, beefy bottom ends, etc. but the truth is that the small blowers were designed specifically for stock engines, and if you keep the RPM at a reasonable limit, there is no reason why the engine wouldn't perform as designed.

could you honestly just put on a new supercharger on a stock 350?

07-31-2006 10:38 PM

Classix_Lover

Hey, guess what? This thread is insanely old I seriously doubt this guy said he put a supercharger on there People say alot of things but never really do it. I wanted to run a blower on mine but realized how much it would set me back just for the blower kit and that huge pricetag didn't include upgrading the rear, improving my traction, not including carbs, etc etc etccc.

07-31-2006 08:44 PM

Rodbuilder

Blow me down!!

I was a custom engine builder in So. Cal. in the 80's and can offer you this ...... If you already HAVE a solid engine, with cast OR forged pistons, you can set up a SMALL huffer on it and make it create NO MORE than 10 pounds of boost and expect it to gain about 125 hp right out of the box. If you push any more than 10 pounds through a bone stock engine, you're sitting on a hand grenade, looking for a place to go off!!! Like Louis Unser taught me in '85 - it's ALWAYS better to huff and engine with low compression and allow the blower to create the horsepowr, than it is to 'blow' a high compression engine and not be able to use all of the boost that the blower is capable of creating. PS: DON'T FORGET TO RE-JET THAT CARBURETOR!!!!!

01-21-2006 07:01 PM

1BAD80

DUH this is over 2 years old.

01-21-2006 04:24 PM

HemmiGremmie

Im by far no expert. But if you click on my project journal, you can see my progress with my 6-71 Weiand blown 355ci sbc motor. Hg

01-21-2006 02:35 PM

THADD

There is a fairly simple answer to your inquiry.
B&M (Now Holley-Weiand) builds a belt driven mini supercharger that will fit under most GM hoods. It was designed to add 100 horsepower to a stock 350 engine, although real world results seem to be in the 40-60% increase.
Anyway you look at it, these mini blowers make cheap horsepower. Depending upon the compression that your engine has, you adjust the amount of boost by changing pulleys.
My blower came with pulleys to make 3 pounds boost. I have built a blower motor with forged blower pistons, good rods and rod bolts, a blower cam shaft, and a good hot ignition and aluminum heads. Because of the parts that I am using, I have bumped the boost up around 10 pounds, and Dyno 2000 says that I am making over 530 horses and 460 ft/lbs.
Well, I don't race dynos, but it does go like stink. ( I accidentally shut down a pal's 11 second Corvette).

There have been a bunch of small block chevy blowers on Ebay this month...Many went for under $800, most went for under $1300. The mini blower gives a quick and hefty horsepower/torque boost to mild engines.

People will tell you about the need for forged pistons, big rods, beefy bottom ends, etc. but the truth is that the small blowers were designed specifically for stock engines, and if you keep the RPM at a reasonable limit, there is no reason why the engine wouldn't perform as designed.

If you can change an intake manifold, you can install one of these mini blowers. The hardest part is the throttle linkage and on a cable type, it is not an issue.
For more info, go to www.Holley.com and click on superchargers or weiand then superchargers.

11-28-2003 11:44 PM

BLOWN64

FIRST YOU NEED TO BRING YOUR COMPRESSION DOWN TO 8 :1 AND GET A NITROUS HP CAM FROM COMP CAM AND IF YOU HAVE AN AUTOMATIC YOU WILL NEED A CONVERTER TO HANDLE THE TORQUE FROM A BLOWER AND DEPENDING ON THE BOOST YOU WILL BE RUNNING I WOULD SAY NO MORE THAN TEN YOU SHOULD SEE 40% TO 65% GAIN IN HP.

ITS ME AGAIN JUST TO LET YOU KNOW IF YOU DONT BUILD IT RIGHT THE FIST TIME LET ME TELL YOU WHAT HAPPEND TO MY 64 FIRST IT FUSED THE CLUTCHES IN MY TRANNY ABOUT 4 MONTHS AGO AND 2 MONTHS AGO IT PUT A HOLE THE SIZE OF A SILVER DOLLAR IN ONE OF MY PISTONS BUT OF COURSE THE ITEMS THAT IAM TALKING ABOUT WERE BASICLY STOCK BUT I KNEW THEY WERE GOING TO GO NOW WHEN I GET THE ENGINE BACK I EXPECT THE REAR END IS NEXT BUT I THINK I WILL BE OK AS LONG AS I DONT PUT SLICKS ON IT AND JUST KEEP SPINNING THE TIRES THROUGH FIRST AND SECOND IN AN AUTOMATIC WITH 3:08 IN THE REAR.

11-28-2003 09:36 PM

73monte

no my dad doesnt pay for anything on my car! i have put all $6000 in it and im still going. so just wait!

11-28-2003 08:25 PM

1BAD80

Please Read.
Thank's.

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"Will 302 heads fit on a 350?"
See #1.

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"Howdy, I got a 350 chevy 4 bolt main. It is in a chevy car with a chevy transmission. It has an intake. How much do you guys think horsepower I am making and torque power abilities at the peakness PRM's?"
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11-28-2003 08:00 PM

Gay-Shark

Re: supercharger....

Quote:

Originally posted by 73monte im looking at getting a supercharger for my monte carlo, its can smoke most car out on the road now, but i want to be able to just half *** it and kill them, so i was thing about getting a supercharger, how much horsepower do you think i could gain.

You are so young and you have so much to learn. Anything you modify to more output you must follow a proven formula or let a pro do it for you. Next question will daddy pay for it.

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